Perovskite solar cells engineering and characterization

Abstract

Organometallic halide perovskites (OMHP) have emerged as an outstanding and promising class of materials for photovoltaic applications, demonstrating efficiencies and cost-effectiveness that rivals traditional solar cell technologies. Despite their rapid advancements, there yet remain some hurdles to be addressed for making them more competitive and cost-effective before commercialization. These include better understanding and addressing of the main factors that drive the efficiency losses and stability deterioration as well as developing various device engineering approaches to tackle them and capitalize more of the unrealized efficiency of perovskite solar cells (PSCs). To that end, this thesis focuses on issues related to process engineering of PSCs, such as the exploration of alternative electron transport material to lower the overall processing temperature and fabrication costs. In addition, controlling the characteristics of the active organo-metallic halide perovskite (OMHP) layer through mixed solvent-antisolvent annealing to enhance the device performance and stability has been investigated. Furthermore, a facile approach to characterize the dominant recombination pathways and quality of interfaces in the functional PSCs through impedance spectroscopy has been developed and experimentally applied on studying devices with different architectures. Overall, this thesis puts forward methodologies to improve PSCs performance and cost-effectiveness as well as offering a handy diagnostic approach toward better understanding of recombination in PSCs.